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Introduction

In the Spring Framework, Spring Beans are the backbone of your application. A Spring Bean is simply an object that is instantiated, assembled, and managed by the Spring IoC (Inversion of Control) container.

Instead of manually creating objects using the new keyword, the Spring container takes over the complete lifecycle of beans—from creation and dependency injection to destruction—enabling loose coupling and easy maintenance.

Ways to Define Spring Beans

Spring provides multiple ways to define and configure beans:

• XML Configuration: Defined using the <bean> tag inside <beans>.
• Annotation Configuration: Defined using annotations like @Component, @Service, @Repository, or @Controller.
• Java-Based Configuration: Defined using @Configuration and @Bean annotations in pure Java classes.

1. Create the Java Bean Class

Here is a simple POJO class named Employee with a name property, setter method, and a display method:

public class Employee {
    private String name;

    public void setName(String name) {
        this.name = name;
    }

    public void displayEmployeeDetails() {
        System.out.println("Employee Name: " + name);
    }
}
  

2. Configure the Bean in Spring XML

In your Spring configuration file (applicationContext.xml), define the bean using the <bean> element, giving it a unique id and configuring its properties:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="employeeBean" class="Employee">
        <property name="name" value="Peter" />
    </bean>

</beans>
  

3. Retrieve the Bean from the Spring Container

Load the application context and retrieve the managed bean using its unique ID:

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App {
    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        Employee emp = (Employee) context.getBean("employeeBean");
        emp.displayEmployeeDetails();
    }
}
  

Watch More Spring Tutorials

• How to Inject String value using Spring dependency injection by constructor? | Spring Tutorial
• How to Inject Dependent Object using Spring dependency injection by constructor? | Spring Tutorial
• In-Depth Comparison: Constructor Injection vs. Setter Injection in Java | Spring Tutorial

---

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What are spring beans? | Spring Tutorial | Spring basics | Spring Framework

What are spring beans? | Spring Tutorial | Spring basics | Spring Framework

What are spring beans? | Spring Tutorial | Spring basics | Spring Framework

What are spring beans? | Spring Tutorial | Spring basics | Spring Framework

How to use ClassPathXmlApplicationContext? | Spring Tutorial | Spring basics | Spring Framework

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Subscribe to Ram N Java on YouTube

Introduction

In Spring applications, the IoC (Inversion of Control) container manages bean creation, wiring, and lifecycle. One of the most popular implementations of ApplicationContext is ClassPathXmlApplicationContext, which loads bean configuration XML files directly from your application's classpath.

In this guide, you will learn how to configure Spring XML files and bootstrap the Spring IoC container using ClassPathXmlApplicationContext in Java.

1. Create the Java Bean Class

Start by creating a standard Java POJO class (for example, HelloWorld) with a message property and a greeting method:

public class HelloWorld {
    private String message;

    public void setMessage(String message) {
        this.message = message;
    }

    public void sayHello() {
        System.out.println("Greeting Message: " + message);
    }
}
  

2. Define Spring XML Configuration (applicationContext.xml)

Place your configuration file in the classpath root (such as src/main/resources) and declare your bean definition:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="helloWorldBean" class="HelloWorld">
        <property name="message" value="Welcome to Spring Framework!" />
    </bean>

</beans>
  

3. Load Context Using ClassPathXmlApplicationContext

Instantiate ClassPathXmlApplicationContext by passing the name of the XML configuration file, retrieve the bean by ID, and execute the method:

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App {
    public static void main(String[] args) {
        // Load the Spring XML configuration from classpath
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");

        // Retrieve the bean from the IoC container
        HelloWorld hello = (HelloWorld) context.getBean("helloWorldBean");

        // Call the method
        hello.sayHello();
    }
}
  

Watch More Spring Tutorials

• What are spring beans? | Understanding Spring Beans | Spring Tutorial | Spring Basics
• How to Inject String value using Spring dependency injection by constructor? | Spring Tutorial
• How to Inject Dependent Object using Spring dependency injection by constructor? | Spring Tutorial

---

Click here to watch on Youtube: 
https://www.youtube.com/watch?v=m74WQGceJvA&list=UUhwKlOVR041tngjerWxVccw 

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0%20http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.ram.core</groupId>
    <artifactId>SpringDemo</artifactId>
    <packaging>jar</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>SpringDemo</name>
    <url>http://maven.apache.org</url>

    <properties>
        <spring.version>5.0.2.RELEASE</spring.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>

        <!-- Spring 5 dependencies -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
    </dependencies>
</project>

Employee.java

package com.ram.model;

/**
 * Spring bean
 *
 */
public class Employee
{
    private String name;

    public void setName(String name)
    {
        this.name = name;
    }

    public void employeeDetails()
    {
        System.out.println("Employee Name =  " + name);
    }
}

applicationContext.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.3.xsd">

    <bean id="employee" class="com.ram.model.Employee">
        <property name="name" value="Peter" />
    </bean>

</beans>

App.java

package com.ram.core;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.ram.model.Employee;

public class App
{
    public static void main(String[] args)
    {
        /*
         * Create a new ClassPathXmlApplicationContext, loading the
         * definitions from the given XML file and automatically
         * refreshing the context.
         *
         * Parameters:
         *
         * configLocation - resource location
         */
        ApplicationContext context = new ClassPathXmlApplicationContext(
                "applicationContext.xml");

        System.out.println("---------------------------------------");

        Employee employee = context.getBean("employee", Employee.class);
        System.out.println(
                "Got employee object from the ApplicationContext(Spring Container)");
        employee.employeeDetails();

    }

}

Output

Apr 09, 2018 8:36:57 AM org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@2096442d: startup date [Mon Apr 09 08:36:56 IST 2018]; root of context hierarchy
Apr 09, 2018 8:36:58 AM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [applicationContext.xml]
---------------------------------------
Got employee object from the ApplicationContext(Spring Container)
Employee Name =  Peter

Click the below link to download the code:
https://sites.google.com/site/ramj2eev2/java_basics/SpringDemo_ClassPathXmlApplicationContext.zip?attredirects=0&d=1

Github Link:
https://github.com/ramram43210/javaee/tree/master/Spring_2018/SpringDemo_ClassPathXmlApplicationContext

Bitbucket Link:
https://bitbucket.org/ramram43210/spring/src/a1d5b66cf948298a0bb7c33e9b2c0967275f5a95/Spring_2018/SpringDemo_ClassPathXmlApplicationContext/?at=master

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How to use FileSystemXmlApplicationContext? | Spring Tutorial | Spring basics | Spring Framework

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Introduction

In Spring applications, the IoC (Inversion of Control) container manages bean creation, wiring, and lifecycle. While ClassPathXmlApplicationContext loads XML definitions directly from the project's classpath, FileSystemXmlApplicationContext allows you to load Spring XML configuration files from the local file system using absolute or relative paths.

In this guide, you will learn how to configure Spring XML files and bootstrap the Spring IoC container using FileSystemXmlApplicationContext in Java.

1. Create the Java Bean Class

Start by creating a standard Java POJO class (for example, HelloWorld) with a message property and a greeting method:

public class HelloWorld {
    private String message;

    public void setMessage(String message) {
        this.message = message;
    }

    public void sayHello() {
        System.out.println("Greeting Message: " + message);
    }
}
  

2. Define Spring XML Configuration (applicationContext.xml)

Create your Spring XML configuration file in a specific file system directory or project root directory and declare your bean definition:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="helloWorldBean" class="HelloWorld">
        <property name="message" value="Hello from FileSystemXmlApplicationContext!" />
    </bean>

</beans>
  

3. Load Context Using FileSystemXmlApplicationContext

Instantiate FileSystemXmlApplicationContext by passing the file system path (relative or absolute) of your XML configuration, retrieve the bean, and execute the method:

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;

public class App {
    public static void main(String[] args) {
        // Load the Spring XML configuration from file system path
        ApplicationContext context = new FileSystemXmlApplicationContext("src/main/resources/applicationContext.xml");

        // Retrieve the bean from the IoC container
        HelloWorld hello = (HelloWorld) context.getBean("helloWorldBean");

        // Call the method
        hello.sayHello();
    }
}
  

Watch More Spring Tutorials

• Spring XML Configuration with ClassPathXmlApplicationContext | Spring Tutorial | Spring Basics
• What are spring beans? | Understanding Spring Beans | Spring Tutorial | Spring Basics
• How to Inject Dependent Object using Spring dependency injection by constructor? | Spring Tutorial

---

Click here to watch on Youtube:
https://www.youtube.com/watch?v=YKI0ssG-3tQ&list=UUhwKlOVR041tngjerWxVccw

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0%20http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.ram.core</groupId>
    <artifactId>SpringDemo</artifactId>
    <packaging>jar</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>SpringDemo</name>
    <url>http://maven.apache.org</url>

    <properties>
        <spring.version>5.0.2.RELEASE</spring.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>

        <!-- Spring 5 dependencies -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
    </dependencies>
</project>

Employee.java

package com.ram.model;

/**
 * Spring bean
 *
 */
public class Employee
{
    private String name;

    public void setName(String name)
    {
        this.name = name;
    }

    public void employeeDetails()
    {
        System.out.println("Employee Name =  " + name);
    }
}

applicationContext.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.3.xsd">

    <bean id="employee" class="com.ram.model.Employee">
        <property name="name" value="Peter" />
    </bean>

</beans>

App.java

package com.ram.core;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;

import com.ram.model.Employee;

public class App
{
    public static void main(String[] args)
    {
        /*
         * Create a new FileSystemXmlApplicationContext, loading the
         * definitions from the given XML file and automatically
         * refreshing the context.
         *
         * Parameters:
         *
         * configLocation - file path
         */
        ApplicationContext context = new FileSystemXmlApplicationContext(
                "D:\\eclipse\\workspace\\SpringDemo\\src\\main\\resources\\applicationContext.xml");

        System.out.println("---------------------------------------");

        Employee employee = context.getBean("employee", Employee.class);
        System.out.println(
                "Got employee object from the ApplicationContext(Spring Container)");
        employee.employeeDetails();

    }

}

Output.txt

Apr 09, 2018 8:16:54 AM org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.FileSystemXmlApplicationContext@2096442d: startup date [Mon Apr 09 08:16:54 IST 2018]; root of context hierarchy
Apr 09, 2018 8:16:56 AM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from file [D:\eclipse\workspace\SpringDemo\src\main\resources\applicationContext.xml]
---------------------------------------
Got employee object from the ApplicationContext(Spring Container)
Employee Name =  Peter